Oil firing arrangement



PIZO, 1937 c. cs H. DE LAVAL l 2,077,826

OIL FIRING ARRANGEMENT Filed July 8, 1932 2 Sheets-Sheet 1 OIL VA LVE 'E THERMOSTAT April 20, 1937. c. G. H. DE AvA| 2 Sheets-Sheet 2 OIL FIRING ARRANGEMENT Filed July 8, 1932 m@ wwmommmmwv Patented Apr. 20, 1937 UNITED STATES OIL FIRING ARRANGEMENT Claude Gustaf Hjalmar de Laval, Stockholm,

Swed

Application July 8, 1932, Serial No. 621,481 In Sweden July 24, 1931 14 Claims.

The present invention refers to an oil firing arrangement of such simplicity both with respect to the construction and in regard to the attendance thereof that combustion of oil can be effected by means of the same also where the demand for heat is so small, or for special reasons such, that the oil ring apparatus as hitherto known cannot be used because of being provided with a considerable number of movable parts generally operated by mechanical means, for

l0 instance by means of electric motors or the like, such parts comprising pumps for the supply of oil and fans for the supply of air, for example. For this reason the apparatus of the latter type could be erected substantially only in such localities where skilled persons were available for the attendance of the apparatus.

This disadvantage is obviated according to the invention, which also facilitates the use of oil furnaces for the heating of small boilers for the heating plants of Villas and so forth, or for dornestic cooking ranges, for example, where skilled attendants generally are not available.

The oil firing plant according to the invention substantially comprises a burner or combustion 'chamberand an accumulatorl connected to a heating means which is in heat-convective relation to one or more conduits or the like for the one or both of the elements (oil and air) participating in the combustion, in such manner that said element or elements are thus heated to a temperature as required for the element in question, in order to ensure the desired combustion conditions with respect to the nature of the oil and the state in which the elements are at the place of combustion.

As stated above, either the oil or the air, or both of them, may be preheated by means of accumulator heat, according to the invention. In certain cases this preheating, for instance of the air, may be adapted in such manner that in the mixing of the air with the oil self-ignition of the oil occurs, special means to ignite the oil, such as an electric spark-plug or the like, being thus rendered superfluous. In certaincases it will be found possible to devise the arrangement so that the oil as well as the air is conducted entirely or in part through one and the same channel extending through the accumulator. The heat accumulator may be in heatconvective relation to an inlet, a conduit or the like for the oil, in such manner that the oil will be gasified by means of heat supplied directly or indirectly from the accumulator, before the oil is ignited at the place of combustion or inthe ccmbustion chamber'. f

This gasification of the oil may take place, for instance, in a gasification chamber or at a. place of gasication in connection with the combustion chamber proper, which gasification chamber or place of gasication may be separated from the combustion chamber, in order to prevent premature ignition.

' The invention will be described more fully in the following with reference to the forms of embodiment illustrated in the accompanying drawings, other features characteristic of the invention being also set forth hereinafter.

In the drawings, Fig. 1 represents a section through a cooking range provided with an oil iiring arrangement according to the invention. Fig. 2 is a section through an oil iiring arrangement, according to the invention, intended forthe boiler of a heating system. Figs. 3 and 4 show modifications of the construction illustrated in Fig. 1.

In Fig. l, 2 designates a container for fuel oil such as petroleum or crude oil of any kind, said container communicating through a conduit 3 having a control valve 4 provided therein, with a burner 5 constructed in the form of a dish. This dish 5 is in direct (metallic) heat-conductive connection withv an accumulator body 'l surrounded by an insulation 5 and consisting, for instance, of cast-iron. Provided above the dish 5 is a combustion chamber 8 communicating through a channel 9, which is preferably made in the form of an annular space extending through the accumulator 1, with the conduit l0 through which the exhaust gases formed in the combustion are led 0H. Air is supplied to the combustion chamber or to therplace of combustion through a channel Il in heat-convective connection with the accumulator 1 and extending, for instance, through the latter, the same being, if desired, formed in the accumulator body in the casting thereof. This channel Il and the channel 9 are formed in such manner that sufficiently large heat transferring surfaces areV obtained for the transference of the heat from the exhaust gases to the accumulator and from` the latter to the combustion air. For this purpose the channels may be provided, for instance, with longitudinally extending ribs or the like.

The supply conduit 3 for the oil to the burner dish 5 is partly extended through the accumulator, as will be seen from the drawings, and is arranged in heat-convective connection with the accumulator. This connection is formed in such manner that suitable preheating of the oil supplied to the burner is obtained. The heating of the oil may be controlled in various ways, for instance as shown in the drawings, by the oil conduit being for a portion thereof provided with a suitably adapted insulation I2 consisting of material of inferior conductivity or, for instance, of air of a vacuum, said material offering a certain resistance to the transference of heat from the accumulator to the oil. Such control may alsobe obtained by an alteration of the size of the heat transferring surfaces, for instance by the conduit 3 being surrounded by a displaceable sleeve I2 which, according to the position in which it is adjusted, is in direct metallic contact with the accumulator material, entirely or in part. The insulating sleeve I2 is preferably movably mounted in the apparatus and has a handle I2 so as to be longitudinally adjustable and thus regulate the heat transference from the accumulator I to the pipe 3.

As stated above, the oil. firing arrangement disclosed is intended for a domestic cooking range, the range plate I3 of which is in heat-conductive connection with the accumulator 'I, the same being, if desired, formed by the upper part of this accumulator and covered by a loose insulated lid I4.

A thermostat, which is designated by I5 in the drawings and which may be constructed in a manner known per se, is in connection with the accumulator as Well as with a closure I6 for the air passage II and with the oil control valve il. Combustion has taken place in the chamber 8 above the disk 5 for so long a period that the temperature of the accumulator l has risen to a denite value, to which the thermostat is adjusted, the latter effects a cut-off of the supply to the place of combustion both of the air through the passage l I and of the oil through the conduit 3. The combustion is thus cut off entirely, and the temperature of the accumulator commences to fall, on the one hand by reason of heat losses due to the insulation 6 surrounding the accumulator, and on the other hand by reason of any heat taken from the cooking range III. The thermostat again opens the oil and air supplies, when the temperature has sunk to a definite valve which, as stated above, is preferably maintained somewhat above that temperature at which the combustion conditions aimed at set in or at which self-ignition of the oil takes place. The air then sup-plied to the burner is heated, when passing through a channel II, to a suitable degree with the aid of accumulator heat. The combustion then continues, until the accumulator temperature has risen to a value at which the thermostat again cuts oif the oil and air supplies. `Starting of this oil firing arrangement may be effected, for instance, by pouring a readily inflammable oil, such as benzine, petroleum or the like, into the container 2, said oil being ignited at the place of combustion and causing heating of the accumulator. According as the temperature of the accumulator rises and the entering combustion air is heated, heavier oils may be supplied to the container 2, whereupon the arrangement operates in the manner above described and heating by combustion of cheap heavy oils is rendered possible. The flow of oil in pipe 3 is limited by the Valve 4 so that complete vaporization will take place in the pipe 3 and the vapor will flow to the burner 20 to be consumed.

Fig. 2 illustrates an embodiment of the invention, in which two oil burners are provided, i. e. a main burner 2i) for the heating of an object to be heated, such* as the boiler 23 of a heating system or the like, and a smaller burner 2I to transfer the requisite heat to the accumulator. As described in connection with Fig. l, fuel oil is supplied tothe main burner 2B from a container 2 through a conduit 3 having a cut-off member 4 provided therein. The combustion air supplied to the main burner is conducted through al channel 22, which in this case also extends through the accumulator 'I in such manner that suitable preheating of the air is obtained. The exhaust gases forming at the combustion in the main burner flow through the combustion chamber 24 and further to the chimney of the plant. The combustion air for the smaller burner ZI is conducted thereto through the channel II Vwhich is also in heat-convective connection with the accumulator, whereby preheating of the air sufficient to attain the desired conditions relative to the combustion is obtained. Further vaporization and burning in the burner 2l is effected in a manner similar to that in burner 223. The exhaust gases from this burner ow through the channel El extending through the accumulator and thus give olf heat to the accumulator, whereupon they are conducted into the combustion chamber 24 or the iiue passage of the main burner. For the control of the temperature variations of the accumulator l surrounded by an insulation 6 in a manner known per se, there is provided a thermostat I5, which in this embodiment operates in such manner as to control or out off the oil and/or air supplies to the smaller burner 2i at a certain maximum temperature of the accumulator, whereas the supply of oil and air to the main burner 2li is not affected. By reason of the yield of heat of the accumulator to the combustion air for the main burner 2U, and on account of the heat loss occurring, a fall of the temperature will then set in. When the temperature has decreased to a certain value, the thermostat again increases or opens the oil and air supplies to the smaller burner, so that control of the accumulator temperature is obtained in the same manner as described with reference to Fig. 1. It will be noted that in this form of the invention, the thermostat I5 determines and controls the heat transfer to the oil supplied to the burner 2B, due to the preheating of the pipe 3 by the accumulator which is maintained at a uniform or desired temperature by the thermostat.

In the modication disclosed in Fig. 3 of the oil firing arrangement shown in Fig. 1, the oil is vaporized by means of heat supplied from the accumulator, before this oil is ignited in the combustion chamber. Provided in the body i of the accumulator is a space 30, into which` opens an oil supply conduit 3 arranged at an inclination to the horizontal plane. This space, in which the oil is vaporized and which in consequence thereto will be termed the vaporization chamber in the following, is in connect-ion with the combustion chamber 8, in which the oil gas forming is ignited.

A wick 3| or the like may be provided within the conduit 3. The oil drops from the conduit 3 upon a vaporization plate 32 which is in heatconductive connection with the accumulato-r 'i and the temperature of which is such that the oil drops are caused to vaporize when hitting the plate. The oil vapor formed flows into a cbmbustion chamber 8 where it is mixed with hot combustion air entering through the conduit Il, and is caused to combust.

In order to prevent ignition of the oil already in the vaporization lchamber 30,- a vertical partition 33 may be arranged between said chamber and the combustion chamber 8, as will be seen from the drawings. Thus the vaporization chamber 30 is separated from the combustion chamber 8, and the oil vapor will be pressed down in the direction of the combustion air, which is of advantage for an effective mixing. By this separation the oil is b-rought into Contact with the combustion air only when the same has been Vaporized, whereby premature ignition of the oil is prevented.

As in the embodiments hereinbefore described, a. thermostat serves to control the temperature variations, for which thermostat two different places of attachment I5a and |517` are shown in the drawings.

In order to ensure the vaporization of the oil at the contact with the vaporization plate 32, and to facilitate starting of the oil ring arrangement, special measures may be taken, as illustrated in Fig. 4. Here, the connection between the vaporizationchamber 3 3 and the combustion charnber 8 takes the form of a nozzle 35, through which the oil vapor formed in the vaporization chamber enters into the combustion chamber, in order to be ignited and combusted therein. The vaporization plate 32 is in heat-conductive connection with a heat accumulating body 36, which is arranged in the combustion chamber 8 right in front of the nozzle 35 and is thus surrounded by burning oil vapor in contact therewith. By this means the temperature of the vaporization plate can be maintained so high that the oil is surely vaporized when dropping upon the plate.

As will be seen from the drawings, the vaporization plate 32 is insulated from the accumulator 'l through an insulation 3l, and between the latter and the vaporization plate 32 there may be provided an electric heater 38 towhich are connected the lead wires 38. When the device is to be started, said heater 38 is heated so that the temperature of the vaporization plate 32 becomes suciently high to ensure vaporization of the oil.

The oil ring arrangement according to the invention may also be provided with a plurality of passages for the o-il as well as for the air, said passages having different surfaces of heat transmission orbeing adapted in such a manner that by selection of the one or the other passage, or of a combination of different passages, the temperature conditions can be adjusted according tor the nature of the oil employed.

The invention is not limited to the embodiments disclosed, but may be modified in many respects within the scope thereof. An oil ring arrangementaccording to the invention may, for instance, be provided with means commonly known from furnace plants, for instance with a so-called accelerator of any suitable type, in order to raise the temperature of the combustion chamber and/or of the vaporization chamber.

What I claim isc- 1. Oil burning apparatus comprising an oil burner, oil and air supply connections for said oil burner, a heat-insulated heat accumulator in heat-transferring relation with at least one of the supply connections whereby the latter is heated to the required temperature, an auxiliary combustion chamber for supplying heat to the accumulator, oil and air supply connections for said auxiliary combustion chamber, and thermostatic means responsive to the temperature of the accumulator for controlling said last-named connections. y

v2. Oil burning apparatusy comprising a heat accumulator consisting of a heat-insulated metallic body provided with a burner for heating external objects and having an auxiliary burner provided with a combustion chamber for heating the accumulator.

3. Oil burning apparatus comprising a heat accumulator consisting of a heat-insulated metallic body provided with a burner for heating external objects and having an auxiliary burner provided with a combustion chamber for heating the accumulator, and means automatically controlling combustion in the auxiliary burner charnber in dependence upon the temperature of the accumulator.

4. Oil burning apparatus comprising a heat accumulator, a burner chamber in said accumulator, a supply pipe for the fuel leading through the body of the accumulator to said chamber, and insulating means surrounding said pipe within the accumulator to diminish the heat-transference from the accumulator to the fuel supplied by said pipe.

5. Oil burning apparatus comprising a heat accumulator, a burner chamber in said accumulator, a supply pipe for a fuel leading through the body of the accumulator to said chamber, and an insulating sleeve surrounding said pipe within the accumulator and longitudinally adjustable to regulate the heat-transference from the accumulator to the fuel supplied to said pipe.

6. Oil burning apparatus comprising a heat accumulator consisting of a heat-insulated metallic body, a burner adapted to suply heat to said accumulator, oil and air conduits leading to the burner and heated by said accumulator, control valves for said conduits, and means for simultaneously operating said Valves including thermostatic means responsive to th-e accumulator temperature.

'7. A heating device of the class described including a heat insulated metallic body, an oil burner associated with the metallic body to heat the same, oil supply conduits and air supply conduits communicating with the burner, said conduits being in heat absorbing relation with said metallic body, a thermostatic device associated with the metallic body so as to be operable in accordance with variations in temperature of the metallic body, and means operatively connecting the thermostatic device to said conduits for controlling the supply of oil and air to the burner in accordance with the temperature of the metallic body.

8. A` heating device of the class described including a heat insulated metallic body pro-vided with a combustion chamber, an oil burner within said chamber to heat said metallic body, an oil supply conduit and an air supply conduit communicating with said burner, said oil supply conduit being in heat absorbing relation with said metallic body, means for controlling the supply of air to the burner, means for controlling the supply of oil to the burner, a thermostatic device associated with the metallic body so as to be operable in accordance with variations in temperature of the metallic body, and means operatively connecting the thermostatic device to the respective controlling means for regulating the supply of the oil and air to the burner in accordance with the temperature of the metallic body.

9. A heating device of the class described including a heat insulated metallic body, an oil burner associated with the body, oil and air supply connections for said oil burner, said connections being in heat absorbing relation with said metallic body, said metallic body having a combustion chamber therein, an auxiliary burner in said combustion chamber for heating said body, conduits for separately conducting oil and air to said auxiliary burner, a thermostatic device associated with the metallic body so as to be operable in accordance with the variations in temperature of the metallic body, and means operatively connecting the thermostatic device to said conduits for controlling the supply of the r oil and air to the auxiliary burner in accordance with the temperature of the metallic body.

l0. A heating device of the class described including a heat insulated metallic body having a burner for heating external objects, oil and air supply connections for said oil burner, said connections being in heat absorbing relation With said metallic body, said metallic body having a combustion chamber therein, an auxiliary burner insaid combustion chamber, for heating said i metallic body, an air supply conduit and oil supply conduit communicating with said auxiliary burner, a therlnostatic device associated With the metallic body so as to be operative in accordance with the variations in temperature of the metallic body, and means operatively connecting the thermostatic device to said conduits for controlling the supply of the oil and air to the auxiliary burner in accordance with the temperature of the metallic body.

ll. A heating device of the class described including a heat insulated metallic body having a burner for heating external objects, oil and air supply connections for said oil burner, said connections being in heat absorbing relation With said metallic body, said metallic body having a combustion chamber therein, an auxiliary burner in said combustion chamber, for heating said metallic body, an air supply conduit and oil supply conduit communicating with said auxiliary burner, a thermostatic device associated with the metallic body so as to be operative in accordance with the variations in temperature of the metallic body, means for controlling the supply of air to the auxiliary burner, means for controlling the supply of oil to the auxiliary burner, and means operatively connecting the thermostatic device to said controlling means for regulating the supply of the oil and air to the auxiliary burner in accordance with the temperature of the metallic body.

12. A heating device of the class described including a heat insulated metallic body provided with a combustion chamber, an oil burner positioned Within said chamber to heat said metallic body, an oil supply conduit and an air supply conduit communicating with said burner, said conduits being in heat absorbing relation with said metallic body, an insulated sleeve surrounding said oil supply conduit and longitudinally adjustable to regulate the heat transference from the metallic body, a thermcstatic device associated With the metallic body so as to be operable in accordance With variations in temperature of the metallic body, and means operatively connecting the thermostat to said conduits for controlling the supply of the oil and air to the burner in accordance With the temperature of the metallic body.

13. A heating device of the class described including a heat insulated metallic body provided with a combustion chamber, an oil burner positioned Within said chamber to heat said metallic body, an oil supply conduit and an air supply conduit communicating with said burner, said conduits being in heat absorbing relation With said metallic body, said oil supply conduit having a vaporizing surface heated by said metallic body, means for controlling the supply of air and gas to the burner, a thermostatic device associated with the metallic body so as to be operable in accordance with variations in temperature of the metallic body, and means operatively connecting the thermostatic device to said last mentioned means for controlling the supply of the oil and air to the burner in accordance With the temperature o the metallic body.

i4. A heating device of the class described including a heat insulated metallic body provided Y with a combustion chamber, an oil burner positioned Within said chamber to heat said metallic body, an oil supply conduit and an air supply conduit communicating With said burner, said conduits being in heat absorbing relation with said metallic body, said oil supply conduit having a vaporizing surface, auxiliary heating means independent of the metallic body for heating said vapcrizing surface, means for controlling the supply of air and gas to the burner, a thermostatic device associated with the metallic body so as to be operable in accordance With variations in temperature of the metallic body, and means operatively connecting the thermostatic device to said last mentioned means for controlling the supply of the oil and air to the burner in accordance with the temperature of the metallic body.

CLAUDE GUSTAF' HJ ALMAR DE LAVAL. 

